Systems and methods for supplying fresh outdoor air into a building structure

ABSTRACT

A method and system for supplying fresh outdoor air into a building structure is disclosed. The method includes monitoring indoor and outdoor temperatures and selectively injecting fresh outside air into a supply line based upon the monitoring. Embodiments include injecting the fresh air using an injection duct within the supply line downstream of a forced air device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 62/802,255, filed Feb. 7, 2019, and incorporated herein by reference in its entirety.

TECHNICAL FIELD

This disclosure relates to heating, cooling and ventilation systems. More particularly, the present disclosure is related to methods and systems for controlling fresh air ventilation.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Heating, ventilation, and air conditioning (HVAC), sometimes referred to as climate control, involves closely regulating temperature, and sometimes humidity, in order to maintain a comfortable, safe and healthy environment inside a building. When heating or cooling a building using a typical forced air HVAC system, air is drawn from within the building into the HVAC unit via return ducting where it is conditioned and forced through the air ducts within the building. Often times, in order to satisfy acceptable indoor air quality requirements, an amount of fresh outside air is required to be ventilated into a house or building.

Continually recirculating and reusing only the air within the building may become problematic because Carbon Dioxide (CO2), Volatile Organic Compounds (VOCs), Radon, and other undesirable element concentrations within the building may exceed acceptable levels over time. Continually reusing only the air within the structure recirculates these pollutant elements within the building and can result in stale and/or hazardous air if the same air is recirculated for too long. Continually reusing only inside air may be beneficial when the inside air has thermal properties which are more desirable, when compared to the outside air. Conversely, intaking fresh outside air and causing indoor air to be expelled may be preferential when the thermal properties of the outdoor air are more desirable, when compared to the inside air.

Recent insulating efficiencies have improved thermal energy losses, but decreased drafts and other outside air intakes, making fresh air intake a necessary consideration when installing or engineering a climate control system for a building.

It is common for residential HVAC systems to intake outdoor air via a duct connecting the return air supply-plenum with an outdoor air hood, located on the outside of the building-envelope. Such configuration relies on a relatively small negative pressure, in the return air ducting, to induce outdoor air through the hood, through the outdoor air ducting, often-times through a barometric damper, and into the HVAC systems air stream by entering the return air supply-plenum.

It is common for roof-mounted, packaged, HVAC units, commonly called “roof-top units” or (RTUs) to intake outdoor air via a hood with a fixed outdoor air damper. It is also common for roof-mounted, packaged, HVAC units to intake outdoor air via a hood which contains electrically actuated mechanical dampers, which are set to act converse of each other, either allowing in outdoor air or recirculating indoor air, or providing for some combination of the two—this configuration, as a whole and along with some additional controls, is commonly called an “economizer”. In all of these examples, the HVAC unit's blower is responsible for inducing the negative pressure region in the system's air-stream, which causes the outdoor air to be taken in. Additionally, in each example provided, the outdoor air always enters the air stream on the intake side of the HVAC unit's blower.

These known venting methods suffer from flow rate inefficiencies and require the heating or air-conditioning devices to draw air from the return air duct. Accordingly, there is a need for improved methods and systems for supplying fresh outdoor air into a building structure via the supply ducting.

SUMMARY

A method and system for supplying fresh outdoor air into a building or structure are disclosed. The method includes monitoring indoor and outdoor temperatures and selectively injecting fresh outside air into a supply line based upon the monitoring. Embodiments include injecting the fresh air using an injection duct within the supply line, downstream of a forced air device.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows an exemplary indoor climate control system for an exemplary building, in accordance with the present disclosure;

FIGS. 2-5 show embodiments of an exemplary fresh air supply injection apparatus, in accordance with the present disclosure;

FIG. 6 is a graphical view of the air pressure within an injection duct and a supply line when fresh air is injected into the supply line, in accordance with the present disclosure;

FIGS. 7 and 8 show exemplary roof-top-units that may be used in conjunction with the above disclosures, in accordance with the present disclosure;

FIGS. 9A-9D show cross-sectional views taken across line A-A of FIG. 3, in accordance with the present disclosure;

FIG. 10 schematically shows the indoor climate control system, in accordance with the present disclosure; and

FIG. 11 shows an exemplary process for supplying fresh outdoor air into a building structure, in accordance with the present disclosure.

DETAILED DESCRIPTION

Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the subject matter of the present disclosure. Appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. The term “unit” and “device” may, but does not necessarily, refer to the same thing.

Various embodiments of the present invention will be described in detail with reference to the drawings, where like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the invention, which is limited only by the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the claimed invention.

As used in the description herein and throughout the claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise: the meaning of “a,” “an,” and “the” includes plural reference, the meaning of “in” includes “in” and “on.” The term “based upon” is not exclusive and allows for being based on additional factors not described, unless the context clearly dictates otherwise. Additionally, in the subject description, the word “exemplary” is used to mean serving as an example, instance or illustration. Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word exemplary is intended to present concepts in a concrete manner.

Referring now to the drawings, wherein the depictions are for the purpose of illustrating certain exemplary embodiments only and not for the purpose of limiting the same, the drawings show an exemplary indoor climate control system 100 for an exemplary building 2 that may help implement the methodologies of the present disclosure. The system 100 includes a forced air device 10, a supply-plenum 12, a trunk supply line 20, a plurality of takeoff runs 22, and a fresh air supply injection apparatus 30. The supply line 20 may be attached to the supply-plenum 12 via a flex connector (i.e. “canvas-connect”), as is known in the art. One skilled in the art will readily recognize that the return air duct 14 may be connected to a trunk line. The device 10 is a furnace in one embodiment, having a blower configured to force air through a supply line 20. In one embodiment, the forced air device 10 is an air conditioning unit configured with a blower to force air through the supply line 20. The system 100 is shown as exemplary, one skilled in the art, upon a careful reading of the teachings herein will recognize that many duct arrangements, and quantities of duct runs, may be included or attached to the system 100. A partial return air duct 14 is shown for ease of description and it should be recognized that the return air duct 14 may include one or more trunk runs, duct branches, boots, grills, and registers.

The supply-plenum 12, the supply line 20, and the plurality of takeoff runs 22 may be formed of sheet metal, but may be formed of duct board, foam board, or any other suitably rigid material. The takeoff runs 22 may be rigid sheet metal ducts or flexible ducts. Flexible ducts are typically formed of a wire-reinforced core, an insulation layer, and an outer sheath. Ducts may terminate at duct boots that connect the ducts to air-terminals (i.e. ceiling diffusers, floor registers, etc.) arranged in the floor, walls, or ceiling of a room.

Oftentimes natural gas burning forced air equipment, like furnaces or roof-mounted packaged HVAC units, will have a manufacturer's rating of the maximum amount of fresh air, typically as a proportion of the total return air, which may pass across the heat exchanger, which utilizes natural gas for heating. Building codes may specify a minimum amount of fresh air to intake for a particular building. The equipment manufacturers may specify a maximum amount of fresh air injection to the return air stream because if the devices receive too much cold air across the heat exchanger the cold winter air may cause the rapid contraction of portions of the heat exchanger and cause the heat exchanger to crack if the temperature differences are too extreme. Known solutions are to install additional, or larger, equipment to meet the minimum amount of fresh air required, while operating under the maximum fresh air allowed for the equipment.

While FIG. 1 depicts the device 10 as a conventional furnace, one skilled in the art should recognize that the teachings herein may be applied to various roof-top-units (RTU), which may be used in conjunction with the device 10 or as an alternative, as may be seen in FIG. 7-8. In one embodiment, an RTU may have a fan 38 inside the device 40 and be configured to direct the injection air into supply line 20, from within the unit's enclosure, drawing air from a hood 42, or by other means, from outside the RTU. In another embodiment, an RTU has a fan inside or outside the unit and directs the injection air into the main supply line 20 from within the unit's enclosure. In one embodiment, the injection duct 36 is wholly located within the RTU, and in another embodiment the injection duct 45 is located partially inside the RTU and partially inside the supply ducting connected to the RTU. In cases where particular zones of an RTU, which services a plurality of zones, may require significantly more outdoor air than another zone of the same RTU (like in a kitchen for example), the injection duct 36 may be located at a main supply duct which only services a particular zone, or a specific set of zones.

In one exemplary embodiment, an RTU has a blower configuration capable of moving a maximum amount of air and an injection fan such as fan 38 shown in FIG. 7, or an exemplary down-blast fan 43 shown in FIG. 8 capable of moving a maximum amount of air which is equal to the amount of air that the blower can move. In this embodiment, an opening of the supply ducting may be larger than the area of the opening for the return ducting. In this embodiment, the supply ducting may have a larger cross-sectional area than that of a typical RTU.

FIGS. 2-5 show the furnace 10, the supply-plenum 12, and a partial view of the exemplary supply line 20. As FIGS. 2-5 show, the fresh air supply injection apparatus 30 can be disposed within the supply line 20 using different duct configurations. The apparatus 30 includes an exterior vent 34 and an injection duct 36 that terminates within a supply line, such as the supply line 20 shown. The injection duct 36 is positioned within a supply line 20 downstream of the exterior vent 34. The apparatus 30 may include any number or arrangement of ducts and connectors to connect the exterior vent 34 to the injection duct 36, such as duct portion 32. For example, the fan 38 may be connected to a reducer duct to increase an inlet duct size of the fan's inlet ducting, relative to the fan's outlet size. In an exemplary embodiment, the cross-sectional area of the fresh air supply injection apparatus' 30 fan's 38 inlet ducting may be double the cross-sectional area of the centrifugal fan's outlet size. The duct 32 may be a rigid or flexible duct. The vent 34 permits outside air to flow into the apparatus 30 or be drawn in by a fan.

In one embodiment, a damper 60 may be included to regulate airflow within the apparatus 30. The damper 60 may be a barometric damper configured to prevent backdraft of air from the supply line 20 from exiting the structure when the fan 38 is off. In one embodiment, the damper 60 may be electronically actuated via the device 50. In one embodiment, the injection fan 38 and/or the damper 60, which is in line with the injection fan's airstream, is controlled such that the intake of outdoor air is ceased under certain conditions, such as an indoor fire, an outdoor fire, a biological emergency affecting outdoor air quality (OAQ), or other relevant conditions.

In one embodiment, one or more filters may be included. In another embodiment, an energy recovery ventilator (ERV) may be included within the apparatus 30, which may be beneficial in applications where a large volume of outside air needs to be introduced into the structure while the structure is occupied.

In one embodiment, fresh air supply injection apparatus 30 is inserted into the supply line 20, or alternatively into the supply-plenum 12, using a mounting plate. The mounting plate may be spot-welded to the injection duct 36 and may be mechanically joined to the supply line 20 or the supply-plenum 12. An injection fan 38 may be connected to the end of the injection duct 36, which may extend about two inches beyond the mounting plate. In this way, when the injection duct 36 is inserted into the supply line 20, the injection fan 38 is very near the supply line 20. In this embodiment, preferably, the injection fan 38 and the injection duct 36 may be roughly balanced at the point of the mounting plate, so that at the mounting plate, the weight of the injection fan plus part of the injection duct 36 on one side of the plate and the length of injection duct 36 on the other side of the mounting plate may roughly weigh the same amount—in this embodiment there would be little or no horizontal force on the mounting plate.

As FIGS. 2-5 show, the fresh air supply injection apparatus 30 includes the injection duct 36 which is an airduct of the fresh air supply injection apparatus 30 that is substantially parallel with the supply line 20 and terminates within the supply line 20. In various embodiments, the injection duct 36 is one to ten feet of duct mounted within the supply line. The injection duct 36 should ideally have a length for preferential gaseous communication of the fresh air intake into the supply line 20 at a flow that is parallel with sidewalls of the supply line 20.

In various embodiments, the fresh air supply injection apparatus 30 includes a duct section 32 connecting the exterior vent 34 to a fan 38. The fan 38 is disposed within the duct in gaseous communication with the exterior vent 34 and configured to inject fresh air into the supply line 20. As described hereinabove portions of the apparatus 30 may be flexible duct including duct section 32. The fan 38 may be a centrifugal fan operated with a variable frequency drive in some embodiments.

FIGS. 2 and 3 show the fresh air supply injection apparatus 30 inserted into the supply-plenum 12 using a 90-degree elbow duct connector. The apparatus 30 may be mounted within the supply line 20 at most any angle or using most any type of duct connector, provided the injection duct 36 within the supply line 20 is substantially parallel with the sidewalls of the supply line 20.

FIG. 4 shows an exemplary fresh air supply injection apparatus 30 illustrating a substantially straight duct connection into the supply-plenum 12 and the supply line 20. The supply-plenum 12 and the supply line 20 are shown in a cutaway view to depict disposition of the injection duct 36 within the supply line 20. The duct section 32 is illustrated as an exemplary flexible duct connecting the vent 34 with the fan 38.

FIG. 5 shows an exemplary fresh air supply injection apparatus 30 illustrating a double 90-degree duct connectors into the supply-plenum 12 and the supply line 20. The supply-plenum 12 and the supply line 20 are shown in a cutaway view to depict disposition of the injection duct 36 within the supply line 20. The duct section 32 is illustrated as an exemplary flexible duct connecting the vent 34 with the fan 38.

FIGS. 9A-9D show cross-sectional views taken across line A-A of FIG. 3. FIG. 9A shows a rectangular cross-sectional shape of the supply line 20 and a circular cross-sectional shape of the injection duct 36. FIG. 9B shows a rectangular cross-sectional shape of the supply line 20 and a circular cross-sectional shape of the injection duct 36 supported by supports 23. FIG. 9C shows a circular cross-sectional shape of the supply line 20 and a circular cross-sectional shape of the injection duct 36 supported with a support 23. FIG. 9D shows a rectangular cross-sectional shape of the supply line 20 and a rectangular cross-sectional shape of the injection duct 36 supported with a support 23.

As FIGS. 9A-9D show, the injection duct 36 is disposed within the supply line 20 at a substantially central position with respect to the sidewalls. In various embodiments, the injection duct 36 may be braced from the sidewalls using, for example, a plurality of mechanical elements 21, which could be spaced over the length of the injection duct 36. The mechanical elements may be braces, hooks, threaded rod, conduct, shelf or other rigid structure configured to hold the injection duct 36. In some embodiments, the injection duct 36 may be rested on the bottom sidewall. In some embodiments, the injection duct 36 is hung from the top sidewall using, e.g., steel wire, threaded rod, a mechanical hook, or other mechanical fastener. As FIGS. 9B-9D show, a threaded rod 23 may be inserted through the supply line 20 and the injection duct 36. The threaded rod, or other like mechanical fastener, may be inserted at various angles in alternative embodiments.

FIG. 6 is a graphical view of the relative air pressure variances which may occur within the injection duct 36 and the supply line 20 when fresh air is injected into the supply line 20 under certain conditions and in some embodiments of the invention. As FIG. 6 shows, injection of the fresh air into the supply line may create a positive pressure region in the center of the supply line, and outwardly going downstream. Initially, the fresh air supply injection apparatus 30 generates the positive pressure region by directing gas into the supply line 20. The injection of the fresh air creates a positive pressure region in the center, and therefore a corresponding negative pressure region on the sides, which diminishes downstream. The movement of the air in the air stream produced by the fresh air supply injection apparatus 30 within this positive pressure region will cause a vortex effect, which will induce a draft of the air within the supply line 20. The induced air flow within the supply line 20 will mix with the air in the air-stream, created by the fresh air supply injection apparatus 30, roughly in inverse proportion to the slowing of the air stream created by the fresh air supply injection apparatus 30, so long as the static pressure of the supply line 20 is relatively low, in consideration of the flowrate of the air stream created by the fresh air supply injection apparatus 30. There can be loss due to static friction with the supply duct 20, but in many embodiments the static friction caused by operating the fresh air supply injection apparatus 30, but not the blower of the device 10, is practically negligible compared to common HVAC system designs. In this embodiment, fresh air injected into the supply duct 20, causes a relatively negative pressure region behind the injection location of the outdoor air injection location, which would induce a draft from the device 10, down the supply line ducting 20, past the fresh air injection duct 36 location, down the supply ducting 20, and out of the supply air terminals. In this embodiment, this pressure change will occur regardless of whether or not the device 10 is actively blowing air, so long as the velocity of the air discharged by the fresh air supply injection apparatus 30 is greater than the supply ducting's 20 air velocity which is resultant from the operation of the device 10

FIG. 7 shows an embodiment with an interior mounted fan 38 and a 90-degree duct component 46 that injects the outdoor air air-stream into the supply ducting. FIG. 8 shows a RTU embodiment with an exterior mounted fan 43 in gaseous communication with duct 45 that may be inserted into the interior supply line ducts within the building structure. Condenser fan grills 41 are shown to provide context, one skilled in the art should recognize that the invention should not be limited thereby.

In various embodiments, the fans 43 and 44 are low differential-pressure fans mounted on a roof or within an attic to selectively remove air from an interior space or ventilate and cool the attic space by bringing in fresh outside air. For example, the fans could be operated in the morning to bring in cool outside air while the low differential pressure attic fan would remove hot air from the building in preparation of high outside temperatures. By dropping the space temperature inside the building prior to the heat of the day, during the early morning hours, and by cooling the attic, something of a thermal-buffer can be created, wherein the attic and the building spaces can absorb substantial heat energy before refrigerant-based cooling would be needed. The net result of the implementation of this precooling can result in more efficient energy consumption.

FIG. 10 schematically shows the indoor climate control system 100. As FIG. 10 shows, an indoor climate control device 50 is communicatively connected with the device 10. In various embodiments the fan 38 and/or the damper 60 may also be communicatively connected to the device 50. Outdoor sensors 52 and indoor sensors 54 are connected to transmit information to the indoor climate control device 50.

The device 50 can includes a processor module and any digital and/or analog circuit elements, comprising discrete and/or solid-state components, suitable for use with the embodiments disclosed herein. One skilled in the art will recognize upon a careful reading of the teachings herein that a radio processor may be included in another embodiment of the device 50 for wireless communication. In one embodiment, a communication adapter and/or transceiver is utilized for wireless communication over one or more wireless communications channels. Although the device 50 is shown as separate components, such an illustration is for ease of description and it should be recognized that the functions performed by the device 50 may be combined on one or more components.

The processor module within the device 50 may be configured to execute various computer programs (e.g., software, firmware, or other code) such as application programs and system programs to provide computing and processing operations for the device 50. In various embodiments, processor module may be implemented as a host central processing unit (“CPU”) using any suitable processor or logic device, such as a general-purpose processor, or other processing device in alternative embodiments configured to provide processing or computing resources to device 50. For example, processor module may be responsible for executing various computer programs such as application programs and system programs to provide computing and processing operations for device 50. The application software may provide a graphical user interface (“GUI”) to communicate information between device 50 and a user. The computer programs may be stored as firmware on a memory associated with processor, may be loaded by a manufacturer during a process of manufacturing device 50, and may be updated from time to time with new versions or software updates via wired or wireless communication.

System programs assist in the running of a computer system. System programs may be directly responsible for controlling, integrating, and managing the individual hardware components of the computer system. Examples of system programs may include, for example, an operating system, a kernel, device drivers, programming tools, utility programs, software libraries, an application programming interface (“API”), a GUI, and so forth.

The memory module is preferably coupled to the processor module. In various embodiments, the memory module may be configured to store one or more computer programs to be executed by the processor module. The memory module may be implemented using any machine-readable or computer-readable media capable of storing data such as volatile memory or non-volatile memory, removable or non-removable memory, erasable or non-erasable memory, writeable or re-writeable memory, and so forth.

A user input device may be coupled to or included with the device 50. The user input device may include, for example, an alphanumeric, numeric key layout and an integrated number dial pad. The device 50 also may include various keys, buttons, and switches such as, for example, input keys, preset and programmable hot keys, left and right action buttons, a navigation button such as a multidirectional navigation button, power/end buttons, preset and programmable shortcut buttons, a volume rocker switch, a ringer on/off switch having a vibrate mode, a keypad and so forth. In one embodiment, the device 50 simply includes an ON and an OFF button, the other controls being activated through a wirelessly connected computing device, such as a mobile device or desktop computer.

An I/O interface may be coupled to the processor module. The I/O interface may include one or more I/O devices such as a serial connection port, an infrared port, Blue Tooth Low Energy (BLE), Mesh Networks, wireless capability, and/or integrated 802.11x (WiFi) wireless capability, to enable wired (e.g., USB cable) and/or wireless connection to a local or networked computer system, such as a workstation or mobile device.

A power supply may be configured to supply and manage power to components of device 50 is preferably coupled to the processor module. In various exemplary embodiments, the power supply may be implemented by a rechargeable battery, such as a removable and rechargeable lithium ion battery to provide direct current (“DC”) power, and/or an alternating current (“AC”) adapter to draw power from a standard AC main power supply.

The device 50 may include one or more transceivers coupled to the processor and an antenna, each transceiver may be configured to communicate using different types of protocol, e.g., Bluetooth®, Near Field Communications, Mesh network, etc., communication ranges, operating power requirements, RF sub-bands, information types (e.g., voice or data), use scenarios, applications, and so forth. For example, the transceiver may include a Wi-Fi transceiver and a cellular or WAN transceiver configured to operate simultaneously. In various embodiments, the transceiver is alternated for a transmitter and/or receiver.

In one embodiment, the device 50 includes a plurality of sensors 52 and 54. The sensors may be directly coupled to the processor or connected through one or more other modules including, e.g., the I/O interface. In one embodiment, a humidity sensor is included. In one embodiment, a temperature sensor is included. In one embodiment, the temperature sensor, is an infrared reader.

The fan 38 may be connected to a separate power supply from the device 50. The fan 38 can include a logic controller and a processor configured to receive operating instructions from the device 50. The fan 38 is configured for selective operation and may be controlled based upon temperature and/or humidity readings from the device 50. In one embodiment, the fan 38 may include one or more operating states such as an ON operating state, an OFF operating state, and/or a plurality of varying power level operating states, which may be reported to the device 50.

The damper 60 may be connected to a separate power supply from the device 50. The damper 60 can include a logic controller and a processor configured to receive operating instructions from the device 50. The damper 60 is configured for selective operation and may be controlled based upon temperature and/or humidity readings from the device 50. In one embodiment, the damper 60 may include one or more operating states, i.e., opening positions, such as a FULLY OPEN operating state, a CLOSED operating state, and/or a plurality of varying open or closed operating states, which may be reported to the device 50.

In various embodiments, the device 50 may be communicatively connected to one or more exterior fan devices 40. The fan devices 40 can include a logic controller and a processor configured to receive operating instructions from the device 50. The fan devices 40 may be configured for selective operation and may be controlled based upon temperature and/or humidity readings from the device 50. In one embodiment, the fan devices 40 may include one or more operating states such as an ON operating state, an OFF operating state, and/or a plurality of varying power level operating states, which all may be reported to the device 50.

The outdoor sensor(s) 52 can include a temperature and/or humidity sensor to monitor local conditions and transmit to the device 50. The indoor sensor(s) 54 can include a temperature and/or humidity sensor to monitor inside the building conditions and transmit to the device 50. The sensor(s) 52 and 54 can communicate information to the device 50 upon determination, at various intervals, upon occurrence of trigger events, upon requests, or the like.

In one embodiment, an electronically commutated motor (ECM) or variable frequency drive (VFD), may be connected to the device 50 and selectively controlled thereby. In this way, the device 50 may control the ECM or VFD to control a total air flow in the supply line 20 such that by modulating either the fan 38, the blower of the device 10, and/or dampers 60, based on differential pressures, static pressures, readings from the sensors 52 and 54, equipment electricity consumption (such as amperage draw), and/or peto tube measurements. In various embodiments total air flow, fan air flow, blower air flow, fan ducting pressure, fan injector pressure, blower return pressure, blower supply pressure, total supply duct pressure, total building pressure (relative to the outdoors), or some combination of these, might be used to determine whether or not to selectively control the fan 38, blower of the device 10, and/or the damper 60.

In one exemplary embodiment, the fan 38 utilizes an ECM, the blower of the device 10 utilizes an ECM, and the HVAC system is capable of variable output or modulating heating and/or cooling. In this embodiment, desired total air flow is maintained though the modulation of the respective ECMs which drive the fan 38 and the blower of the device 10. In one embodiment, desired discharge air temperature of the supply line 20 is maintained by the combination and the use of, the modulation of injection fan, the modulation of the blower of the device 10, and/or the modulation of the heating and/or cooling devices. Additionally, air velocities at the point of the air terminals may have significant impact on the efficiency and the noise produced by the system. For example: if the air velocity at the air terminal is too high, then excessive noise may result, but if the air velocity is too low, significant air stratification might occur.

In one embodiment, the device 50 may control the ECM to deliver a constant flow of air, in units of cubic feet per minute (CFM) despite any minor changes in static pressures. A constant, relatively consistent volumetric air flow regardless may be provided by adjusting or modulating the rotations per minute (RPM) of the blower of the device 10 appropriately and/or the fan 38. In some embodiments, real-time modulation of the CFM setpoint may be performed either directly or indirectly by the device 50.

In some embodiments, the device 50 controls the blower of the device 10 and the fan 38 in an inversely proportional manner based upon CFM output. For example, the fan 38 may be controlled to increase CFM output, while the blower of the device 10 is controlled to reduce positive CFM output. In another exemplary embodiment the device 50 maintains blower CFM rates only slightly above the freezing point of the evaporator coil, thereby providing for a more effective means of dehumidifying the air stream. In one exemplary embodiment, the device 50 may be selectively configurable to allow for maximum output of both the blower of the device 10 and the fan 38. In one embodiment, VFDs are utilized to control fan outputs much in the same was as described herein where expressed relating to ECM control and operation and in another multi-speed motors are used, as one skilled in the art will recognize upon careful examination of the teachings herein disclosed.

For CFM setpoint control requiring proportionality, or any deviation based on proportionality, temperature sensors and/or peto tubes or other techniques for determining volumetric flow may be utilized based on the following:

% VFODA=(SAT−MAT)/(SAT−ODAT)*100

Where

ODAT represents an outdoor air temperature which can be measured using sensor 52, and SAT represents a supply air temperature, which may be measured from sensor 54 or a sensor within the supply line 20, downstream of an end of the duct 36, and MAT represents a mixed air temperature which may be measured from a sensor within a supply-plenum, and % VFODA represents the percent of volumetric flow of outdoor air.

In one embodiment, the device 50 may calibrate a natural variation in accuracy between the SAT sensor and the MAT sensor by disabling the injection of outdoor air and operating the blower for a short period of time before making provision in the computer code such that the two sensors read the exact same value, or a value which is closer to the same. In this manor, though a resistance-based thermistor may have differing resistance values, as far as the computer code is concerned, at the time of calibration, those two thermistors will effectively have the same resistance in the computer code functionality. In one embodiment the calibration time may last for one minute, and in another the calibration time may last for three minutes, etc.

In one embodiment a structure equipped with fresh air supply injection apparatus 30 also has a barometric relief damper which allows for the relief of pressure from within the structure via the discharge of indoor air to the outdoors.

FIG. 11 shows an exemplary process 200 for supplying fresh outdoor air into a building structure 2. The process 200 may be utilized in conjunction with the system 100, the device 50 and one or more of the sensors 52 and 54.

The process 200 may be initialized 202 manually or automatically in accordance with other executing processes. In one embodiment, the process 200 is initialized 202 by simply turning the device 50 to an ON operating state. In one embodiment, the process 200 is initialized by receiving instructions from a computer program to start. In one embodiment, one or more criteria may be used to initiate the process 200 including, e.g., temperature below a threshold for a predefined time period at within a pre-defined time range of a day.

At step 204, in one embodiment, after initiation 202 of the process 200, the device 50 receives operating states of connected device, e.g., the device 10, the fan 38, a damper 60, an exterior fan 40, and one or more sensors 52 and 54. In one embodiment, the device 50 includes pre-defined indoor temperature and humidity set-points. In one embodiment, the device 50 receives set-points from a user.

At step 206, the device 50 receives monitored information from one or more of the connected devices. The sensors 52 and 54 can send temperature or humidity data. The device 10 can send set-points, in some embodiments.

At step 208, the device 50 determines whether the fan 38 should be transitioned to an ON operating state. In various embodiments, which may depend upon a particular building setup, environmental conditions of the area, time of year, etc., the decision to transition to the ON operating state may be based upon receive information from the sensors 52 and 54, temperature set-points, and time-of-day. In one embodiment, the device 50 transitions the Fan 38 to an ON operating state if the indoor temperature is greater than a predefined threshold, the outdoor temperature is less than a predefined threshold, and the setpoint is less than an indoor temperature or close to the indoor temperature. In one embodiment, humidity of the indoor and outdoor sensors are used in conjunction with temperature to determine whether or not to transition the fan 38 to the ON operating state. In one embodiment, humidity data may be used to adjust temperature readings to generate a metric, which may then be used to determine whether or not to transition the fan 38 to the ON operating state.

In one embodiment, the device 50 is configured to transition the fan 38 from the OFF operating state to the ON operating state at a pre-defined time of day. In one embodiment, the device 50 is configured to transition the fan 38 from the OFF operating state to the ON operating state at a pre-defined time of day only when the temperature and humidity readings are preferential. In one embodiment, the device 50 transitions the fan 38 to the ON operating state for a predefined threshold time, and once elapsed, transitions to the OFF operating state. Likewise, in various embodiments, the device 50 may transition the exterior fan 40.

At step 210, the device 50 transitions the fan 38 to an ON operating state. In various embodiments, the device 50 may continue monitoring temperature, humidity, and operating state information to determine when and whether to transition back to the OFF operating state.

In one embodiment, the device 50 may activate the fan 38 without activating the blower of the device 10. The fan 38 may be energized before, during, or after a call for cooling, when outdoor air temperatures are desirous for precooling.

The schematic flow chart diagrams included herein are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented process. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types may be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the process. For example, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted process. It will also be noted that each block of the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and program code.

Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more blocks, or portions thereof, of the illustrated Figures. For example, steps 204 and 206 may be executed concurrently in some embodiments.

Additionally, examples in this specification where one element is “coupled” to another element can include direct and indirect coupling. Direct coupling can be defined as one element coupled to and in some contact with another element. Indirect coupling can be defined as coupling between two elements not in direct contact with each other, but having one or more additional elements between the coupled elements. Further, as used herein, securing one element to another element can include direct securing and indirect securing.

As used herein, the “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and/or mutually inclusive, unless expressly specified otherwise. Further, the term “plurality” can be defined as “at least two.”

As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method, and/or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module,” or “system.” Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having program code embodied thereon.

Many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

Modules may also be implemented in software for execution by various types of processors. An identified module of computer readable program code may, for instance, comprise one or more physical or logical blocks of computer instructions which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module.

Indeed, a module of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. Where a module or portions of a module are implemented in software, the computer readable program code may be stored and/or propagated on in one or more computer readable medium(s).

The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

More specific examples of the computer readable medium may include but are not limited to a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and/or store computer readable program code for use by and/or in connection with an instruction execution system, apparatus, or device.

The computer readable medium may also be a computer readable signal medium. A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical, electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing

In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electro-magnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

As one skilled in the art may readily understand upon careful review of the teachings herein disclosed, dimensions, lengths, and other units of measure and shape are given for illustrative purposes. For example, in cases where round ducting is specified, one skilled in the art may understand that square or rectangular duct may be used instead of round duct, and where a specific unit of measure is given, one skilled in the art my substitute that measure with another measure and still fall within the teachings of this disclosure. Likewise, where centrifugal fans are specified, other fan types may be used.

While the foregoing disclosure discusses illustrative embodiments, it should be noted that various changes and modifications could be made herein without departing from the scope of the described embodiments as defined by the appended claims. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within scope of the appended claims. Furthermore, although elements of the described embodiments may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated. Additionally, all or a portion of any embodiment may be utilized with all or a portion of any other embodiments, unless stated otherwise. 

1. An indoor climate control device, comprising: one or more processors; memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for: monitoring indoor and outdoor temperatures; and selectively injecting fresh outside air into a supply line based upon the monitoring.
 2. The indoor climate control device of claim 1, further comprising: receiving an operating state status of a fan within a ducting apparatus configured for gaseous communication between an exterior vent and the supply line.
 3. The indoor climate control device of claim 1, wherein the injecting is at an injection duct within the supply line downstream of a forced air device.
 4. The indoor climate control device of claim 1, wherein injecting fresh outside air into a supply line based upon the monitoring is executed by transmitting a command to a fan in gaseous communication between an exterior vent and the supply line.
 5. The indoor climate control device of claim 1, wherein selectively injecting fresh outside air into a supply line based upon the monitoring is executed using an injection duct having a circular cross-sectional shape.
 6. The indoor climate control device of claim 1, wherein the injection duct is centrally disposed within the supply line via one or more mechanical element.
 7. The indoor climate control device of claim 1, wherein the injection duct is disposed within the supply line on a bottom wall thereof.
 8. The indoor climate control device of claim 1, wherein the injection duct is substantially parallel to the supply line.
 9. The indoor climate control device of claim 1, wherein the injection duct is substantially parallel to the supply line, encased within the supply line, centrally disposed within the supply line, and terminates downstream of a forced air device within the supply line, which has a length greater than the injection duct, wherein injecting fresh outside air into a supply line based upon the monitoring is executed by transmitting a command to a fan in gaseous communication between an exterior vent and the supply line, and wherein selectively injecting fresh outside air into a supply line based upon the monitoring is executed using an injection duct having a circular cross-sectional shape and is centrally disposed within the supply line via one or more mechanical elements.
 10. An indoor climate control system having a supply line, comprising: an exterior vent; and a duct run connected to the exterior vent and terminating within the supply line.
 11. The indoor climate control system of claim 10, further comprising: a fan configured to selectively draw in outside air.
 12. The indoor climate control system of claim 10, further comprising: a damper within the duct run proximate to the exterior vent.
 13. The indoor climate control system of claim 10, wherein the duct run is disposed through a supply-plenum to the supply line.
 14. The indoor climate control system of claim 10, wherein the duct run has an end in a circular cross-sectional shape.
 15. The indoor climate control system of claim 10, wherein the duct run is centrally disposed within the supply line via one or more mechanical elements.
 16. The indoor climate control system of claim 10, wherein the duct run is disposed within the supply line on a bottom wall thereof.
 17. The indoor climate control system of claim 11, wherein the fan is configured to inject fresh air into the supply line at a flow rate to cause a vortex effect within the supply line.
 18. An indoor climate control system for a forced air system having a return line and a trunk supply line, the system comprising: an exterior vent configured to drawn in fresh outside air; a fan; and a duct run connected to the exterior vent and terminating within the supply line, wherein the fan is disposed within the duct run in gaseous communication with the exterior vent and configured to inject fresh air into the supply line, wherein a portion of the duct run is parallel with sidewalls of the supply line.
 19. The indoor climate control system of claim 18, wherein the duct run is centrally disposed within the truck supply line via one or more mechanical elements, and wherein the duct run has an end in a circular cross-sectional shape.
 20. The indoor climate control system of claim 18, wherein the duct run is disposed through a supply-plenum to the supply line, and wherein the system further comprises a damper within the duct run proximate to the exterior vent. 